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Well, I had nothing to do (like usual) today so I decided to type out some interesting articles about car parts and stuff which appeared on the newspapers a couple of days back. Ill update this if anything new pops up 
Thank you to my local newspaper for this : The New Straits Times
Know Your Car
Turbo versus Supercharger
All engines draw air into the cylinders. It is mixed with petrol or diesel to enable the explosions that give the car its power. Most ordinary cars suck in air at normal atmospheric pressure: as the piston moves down in the cylinder, air is pulled in through the valves.
However, some engines use systems which force air into the cylinder under pressure. More air means that more fuel can be added (the ratio of fuel to air remaining the same). This increases the power of the explosions, thus the cars performance. This process is known as forced induction, and there are two very different systems available.
The first and most common is the turbocharger. This is a turbine which is spun by the flow of exhaust coming out of an engine. Its power is used to drive a fan, which blows air into the engine.
By contrast, a supercharger is a mechanical pump run by a belt from the engine itself. Unlike a turbo, which can spin at over 100,000rpm, a supercharger is geared to work at not much more that engine idle speed, but its aim is the same: to dramatically increase the amount of air ingested into the engine to create a bigger bang when it is combined with fuel and ignited.
Each system has its own advantages and drawbacks. Turbos are smaller, lighter and more efficient than superchargers but require a substantial flow of exhaust gas to work properly: at low revs turbo engines feel sluggish and even at high engine speeds take a small but discernible time to respond to the throttle.
Superchargers, by contrast, works from idling revs and have instantaneous throttle response. On the negative side, because they are powered by the engine itself they can significantly increase fuel consumption.
Differentials
All road cars have differentials, and would be undriveable without them.
Driving in a circle, the wheels on the inside have less distance to travel than those on the outside and therefore must turn more slowly.
In a front-wheel drive car the rear wheels will do this naturally but without a differential the front wheels would rotate at the same speed, causing the car to skid. A differential enables each driveshaft to rotate at different speeds appropriate to the corner.
However, normal or open differentials can be caught out. If there are differing levels of grip available to each tyre when your car has one front tyre on ice and the other on dry tarmac an open differential will allow the tyre on the ice to spin while the tyre on tarmac doesnt rotate at all.
This is why many off-road cars have differential locks that can be activated by the driver in difficult conditions and make both wheels on an axle rotate at the same speed regardless of available grip. This would enable the car parked with one tyre on ice the pull away.
Many 4X4s also have a center differential to control the drive sent to the front and rear axles. If the front tyres lose traction more power is sent to the rear, lessening the fronts workload and restoring grip.
The last kind of differential often mentioned in road tests is the limited-slip differential. Unlike an open differential that doesnt limit the speed difference between wheels on the same axle, a limited-slip differential restricts this slip.
By avoiding power-wasting wheelspin, this can improve traction when accelerating away from corners in low grip conditions and is, therefore, favoured for racing and sports cars.
BTW Members please point out if there are any mistakes!
Thank you to my local newspaper for this
: The New Straits Times Know Your Car
Turbo versus Supercharger
All engines draw air into the cylinders. It is mixed with petrol or diesel to enable the explosions that give the car its power. Most ordinary cars suck in air at normal atmospheric pressure: as the piston moves down in the cylinder, air is pulled in through the valves.
However, some engines use systems which force air into the cylinder under pressure. More air means that more fuel can be added (the ratio of fuel to air remaining the same). This increases the power of the explosions, thus the cars performance. This process is known as forced induction, and there are two very different systems available.
The first and most common is the turbocharger. This is a turbine which is spun by the flow of exhaust coming out of an engine. Its power is used to drive a fan, which blows air into the engine.
By contrast, a supercharger is a mechanical pump run by a belt from the engine itself. Unlike a turbo, which can spin at over 100,000rpm, a supercharger is geared to work at not much more that engine idle speed, but its aim is the same: to dramatically increase the amount of air ingested into the engine to create a bigger bang when it is combined with fuel and ignited.
Each system has its own advantages and drawbacks. Turbos are smaller, lighter and more efficient than superchargers but require a substantial flow of exhaust gas to work properly: at low revs turbo engines feel sluggish and even at high engine speeds take a small but discernible time to respond to the throttle.
Superchargers, by contrast, works from idling revs and have instantaneous throttle response. On the negative side, because they are powered by the engine itself they can significantly increase fuel consumption.
Differentials
All road cars have differentials, and would be undriveable without them.
Driving in a circle, the wheels on the inside have less distance to travel than those on the outside and therefore must turn more slowly.
In a front-wheel drive car the rear wheels will do this naturally but without a differential the front wheels would rotate at the same speed, causing the car to skid. A differential enables each driveshaft to rotate at different speeds appropriate to the corner.
However, normal or open differentials can be caught out. If there are differing levels of grip available to each tyre when your car has one front tyre on ice and the other on dry tarmac an open differential will allow the tyre on the ice to spin while the tyre on tarmac doesnt rotate at all.
This is why many off-road cars have differential locks that can be activated by the driver in difficult conditions and make both wheels on an axle rotate at the same speed regardless of available grip. This would enable the car parked with one tyre on ice the pull away.
Many 4X4s also have a center differential to control the drive sent to the front and rear axles. If the front tyres lose traction more power is sent to the rear, lessening the fronts workload and restoring grip.
The last kind of differential often mentioned in road tests is the limited-slip differential. Unlike an open differential that doesnt limit the speed difference between wheels on the same axle, a limited-slip differential restricts this slip.
By avoiding power-wasting wheelspin, this can improve traction when accelerating away from corners in low grip conditions and is, therefore, favoured for racing and sports cars.
BTW Members please point out if there are any mistakes!
